In the bomb disposal field it is frequently desirable to remove a device that is suspected of being an explosive device from a building or other location in which it has been found. One approach to removing such an article involves the use of pulleys and lines or ropes to move the device remotely. The pulleys and lines can be set up to define a complex path through which the article can be pulled. In order to allow the article to move along the complex path, it is necessary that the pulleys be able to release the line travelling through each pulley, at the desired time, without being visible or separately manipulated by the user.
U.S. Pat. No. 5,201,496 discloses a line release pulley. The pulley has a pivoting cheek plate that allows release of a line. However, there is no means of ensuring that the pivoting cheek plate opens only at the desired time and that the line remains released.